The Alpha Filters plugin gives you a flexible capability to filter pages & users by letters, numbers and letter combinations (syllable-based). You can also assign your own styles to the filter span elements.
Authors: esclkm, Kalnov Alexey, Cotonti Team
Github: https://github.com/Alex300/cotonti-alphafilters
Example for users.tpl:
<!-- IF {PHP|cot_plugin_active('alphafilters')} AND {PHP.cfg.plugin.alphafilters.turnOnUsers} == 1 --> <div class="margin10 small text-center"> {PHP.L.alphafilters_byFirstLetter}: {ALPHAFILTER_1} {ALPHAFILTER_2} <!-- IF {ALPHAFILTER_3} --><br />{ALPHAFILTER_3}<!-- ENDIF --> {ALPHAFILTER_RESET} </div> <!-- ENDIF -->
Plugin example: